This project involves the investigation of cellular properties underlying integration and output pattern production in a small (30-celled) neural system, the stomatogastric ganglion of the spiny lobster. Study will be made of: 1. Plateau potentials, slow regenerative active depolarizng membrane responses that drive bursts of impulses: The ionic bases, kinetics, and contributions to pattern production of plateaus will be included. 2. Induction of plateau properties by central input. Organization, synaptic mechanisms, kinetics, and network function (including roles as command fibers) of inducing inputs will be included. 3. Other mechanisms of descending pattern control in the ganglion, including inductive modulation of other cellular properties, control of plateaus by conventional synapses, and action of conventional synapses on ganglion activity. 4. Other cellular mechanism of pattern production including delaying conductances, repetitive firing, and conventional synaptic mechanisms.